RT Journal Article SR Electronic(1) A1 Ulitzur, S. A1 Shilo, M.YR 1964 T1 A Sensitive Assay System for Determination of the Ichthyotoxicity of Prymnesium parvum JF Microbiology, VO 36 IS 2 SP 161 OP 169 DO https://doi.org/10.1099/00221287-36-2-161 PB Microbiology Society, SN 1465-2080, AB SUMMARY: The activity of Prymnesium parvum ichthyotoxin and its dependence on various cofactors has been studied. Spermine or other polyamines have a marked synergistic effect on the ichthyotoxic activity. Of the cations studied, Ca2+ and Mg2+ increased ichthyotoxic activity, while Na+ inhibited. Changes in pH value had a profound influence, ichthyotoxicity increasing at least 400-fold as the pH value was increased from 7 to 9. A sensitive bioassay for the estimation of P. parvum ichthyotoxin has been developed for use in the laboratory and under field conditions., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-36-2-161